This application relates to an apparatus for heating a structure such as a dwelling, and particularly to an apparatus for heating a structure by means of solar energy.
There has been considerable concern that conventional sources of energy for heating dwellings will not be suitable for meeting with future demands, because of the scarcity of the raw materials needed to generate such energy, and because of the greatly increased expense which new exploration for sources of those raw materials is expected to result. There has therefore been a considerable demand for alternate sources of heating energy, and particularly alternate source of heating energy which makes use of a readily available energy source, solar energy. In fact, there are many who believe that solar energy represents the only practical long range solution to the present energy crisis.
In recent years there have been numerous and varied types of solar powered heating systems suggested.
One such system is disclosed in U.S. Pat. No. 3,894,685. According to this patent a series of cylindrically shaped heat collectors are disposed to absorb solar energy. A flow of air is then directed over the exposed outer cylindrical ends of these collectors and thereby transfers heat from the collectors to the air. In this system, the flow of air passes between the open ends of the collectors and the underside of the heat insulating cover structure and minimal air passes into contact with the outer walls of the collectors.
In addition to the system of U.S. Pat. No. 3,894,685, various other types of systems have been suggested in which a flow of air is passed over respective surfaces of the solar energy collectors and between the solar energy collectors and the insulating cover without being directed into contact with the solar energy collector. Heated air from the collectors is thus free to radiate into contact with the underside of the insulating cover. Heated air in contact with the insulating cover serves to transfer at least a portion of its heat energy thereto, and such heat energy is thereby lost from the heating system and is therefore not available for heating the structure.
In addition, in systems where the primary air flow is directed between the solar energy collector and the insulating cover it is possible for particulate matter in the air (such as dust, for example) to be deposited on the surface of the solar energy collector. A build-up of such particulate matter may ultimately impair the efficiency of the system.